A new magnetic solid phase extraction sorbent material (MSPE) based on sol-gel magnetite@graphene-tetraethoxysilane-methyltrimethoxysilane sorbent (Fe3O4@G-TEOS-MTMOS) was successfully prepared and applied for the simultaneous removal of selected polar and non-polar organophosphorus pesticides (OPPs) from several water samples. The new in-house synthesized Fe3O4@G-TEOS- MTMOS MSPE sorbent was characterized using FT-IR, XRD, EDX and FESEM. The four OPPs test analytes namely phosphamidon, dimethoate, diazinon and chlorpyrifos were extracted using the synthesized MSPE sorbent and determined by gas chromatography-micro electron capture detector (GC-�ECD). Critical MSPE parameters optimized included types of solvent, sample volume, extraction time and elution time. Under optimum conditions, the sol-gel hybrid TEOS-MTMOS modified Fe3O4@G MSPE sorbent showed linearity in the range 100-1000 pg mL-1 for phosphamidon and dimethoate, 10-100 pg mL-1 for chlorpyrifos and diazinon, with limit of detection (S/N = 3) of 19.8 pg mL-1 for phosphamidon, 23.7 pg mL-1 for dimethoate, 1.4 pg mL-1 diazinon and 2.9 pg mL-1 for chlorpyrifos. The precision achieved for intra-day (n=3) and inter-day (n=15) analysis were RSD 1.3� 8.7%, and 7.6- 17.8%, respectively. The new sol-gel hybrid graphene-based MSPE sorbent was proven to have a high adsorption capacity (54.4 -76.3 mg g-1) for all the selected OPPs. High recoveries were achieved for the OPPs using the in-house synthesized Fe3O4@G-TEOS-MTMOS from tap water (103-110%), river water (100-105%), lake water (89-102%) and sea water (83-100%) samples.

New organic-inorganic hybrid magnetite@graphene-tetraethoxysilane-methyltrimethoxysilane magnetic solid phase extraction sorbent for simultaneous analysis of polar and non-polar organophosphorus pesticides

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.